3161.9% is the change from 21 to 685
Calculation steps:
[( 685 - 21 ) ÷ 21] x 100 = 3161.9%
Formula
Percentage change = [(685 - 21) / 21] x 100
Subtract the new number by the original number
685 - 21 = 664
664 ÷ 21 = 31.61904761904762
31.61904761904762 x 100 = 3161.9%